Doorcheck device



Dec. 8, 1931. J. H. VANDER VEER DOORCHECK DEVICE Filed June 50, 1951 BY h s ATTORNEYS fiai ug g.

F R0 m E mv r n M J Patented Dec. 8, 1931 UNITED STATES PATENT OFFICE JOHN H. VANDEB Wm, 01 WESTFIELD, NEW JERSEY, ASSIGNOB '].0 NATIONAL PNEUMATIC COMPANY, OF NEW YORK, N. Y., A CORPORATION OF WEST VIRGINIA DOORCHEOK DEVICE Application filed June 30,

This invention relates in general to door check devices.

One of the objects of this invention is the provision of a door check mechanism for use on heavy doors such as Pullman car doors and the like, which are provided with heavy pneumatic or spring door checks for closing them and holding them closed.

Another object of this invention is the provision of a motive device of limited power for aiding in the opening of doors which are provided with strong door cheeks and for closing the doors and holding them closed.

Another object of this invention is the provision of electro-magnetic apparatus of this type which is automatically operated in connection with the operation of the door latch.

These and many other objects as will appear from the following disclosure are secured by means of this invention.

This invention resides substantially in the combination, construction, arrangement and relative location of parts all as will be described in detail hereinafter.

Referring to the drawings Figure 1 is an elevational view of a portion of the door and the motive device in section connected thereto as well as the electric and air circuits employed;

Fig. 2 is a longitudinal central cross-sectional view through the door latch.

Where swinging doors are provided with automatic closing devices such. as spring return door checks, it often happens that the pressure which must be exerted upon the door in order to open it against the door check is considerable. The return spring of the door check for such doors, especially such as those on Pullman ears, for example, and other railway vehicles, must exert considerable pressure on the door in order to insure the closing of the door under all conditions and the holding of the door closed.

The prime object of this invention is to provide a limited external power source to close the door and hold it closed and to aid in opening the door against the resistance of the door check. The force exerted by the power device is limited so that in case of an be better understood in connection 1931. Serial No. 547,845..

emergency and the failure of correct operation thereof the door may be pushed open against the resistance of the power device.

The general nature of the invention will with the drawings.

At 1 is indicated the door frame upon which is mounted by means of the hinges 3 the door 2 so that it may be swung away from and towards the door frame. At 4 mounted on the door frame is the latch bolt keeper 4. Within the lock casing 5 is a longitudinally slidable bolt 6 which projects into the keeper when the door is closed and locked. The latch bolt is provided with a recess 7 in which a suitably shaped cam 9 rests. This cam is mounted on the shaft to which the door knobs 8 are secured. The bolt 6 is mounted within the lock casing 5 so that when either door handle 8 is rotatedthe bolt 6 slides out of engagement with the keeper by reason of the action of cam 9 on the recess 7 of the bolt. The latch bolt is provided with an integral reduced extending rod 10 on which is mounted a contact disk 11 insulated therefrom. The end of this rod slidably fits within a depending bracket for guidance and a spring 14 is interposed between the disk 11 and the bracket so as to normally urge the bolt 6 into projected position. At 12 is a block of insulated material supported within the lock casing and provided with two projecting contact fingers 13 in a position to be engaged by the contact disk 11 when the latch bolt is withdrawn from the keeper.

At 15 is a plate secured to the door 2 at a suitable point. A link 16 is pivotally connected to this plate at one end and at the other end to a second link 17 which, in turn, is connected to the shaft to which is secured the segmental gear 24 within the motive device 18. The motive device comprises a casing having the cylinders 19 and 20 arranged in alignment. Cylinder 20 is of a slightly larger diameter than cylinder 19 for reasons to be pointed out later. Within the cylins dcrs' 19 and 20 are the pistons 22 and 21 respectively, united together by means of a rigid shaft 23 which has a gear rack formed on its upper surface for engagement with the teeth of the segmental gear 24. The piston Cylinder 20 is closed by means of a closure member 27 which is provided with a hollow extension closed by means of a threaded plug 28. Within this extension is a slidably mounted disk 30 which is normally urged away from the plug by the coil spring 29. The closure member 27 is provided with a chamber 31 and an extending chamber 35 which is provided with a restricted discharge port 36. Within the chamber 5 is a slidably mounted plunger 34 formed with a valve surface at its lower end to engage with the valve seat in the casing 35. A second valve surface 32 is connected to the plunger by means of a rod which, in turn, seats on a second valve seat in the casing. A spring 48 normally holds the plunger and the valves 32 and 33 in the position so that valve 32 is seated and valve 33 is unseated. A solenoid winding 37 surrounds the plunger 34 and is connected at one terminal by wire 38 to one of the contact fingers 13 and at its other terminal by wire 39 to one side by a suitable current source 40. The other side of this current source is connected by wire 41 to the other contact finger 13 in the lock.

At 42 is a source of compressed air which is connected by means of pipe 44 to a choke device 43 to the passage 45 of the closure member 27. This passage 45 opens into the chamber 31. A branch pipe 46 connects pipe 44 with cylinder 19. Cylinder 20 is connected to the atmosphere through the passage 47 which opens into the casing 35 above the seated valve 32. As already noted the easing 35 is opened to the atmosphere through the restricted port 36.

In the operation of the device the handle 8 is revolved in either direction to withdraw the latch bolt 6 from the keeper 4 to unlock the door. This movement of the latch bolt causes contact 11 to bridge the contact fingers 13 to complete the circuit to the solenoid winding 37 in an obvious manner. This causes plunger 34 to be pulled downwardly unseating valve 32 and seating valve 33. 'As a result passage 47 which is normally open to the atmosphere is closed off from the atmosphere and connected to the chamber 31. Air then flows from the source 42 through pipe 44, passage 45 into chamber 31 and from chamber 31 through passage 47 into cylinder 20. Cylinder 19 is. of course, always connected to the fluid pressure source through pipe 46. As a result the same fluid pressure is supplied to both cylinders.

Piston 21 is of a slightly larger diameter than piston 22 so that when the door is unlocked and pulled open the motive device supplies just enough power to overcome the resistance to movement which such a door naturally has. For. example, there is suflicient power to operate the motive device and overcome its directional resistance and also to overcome the resistance of the door check as well as any other normal frictional resistances to movement which the door may have. Thus a person may easily open the door without having it forcibly opened with the danger of striking someone. When he releases the door the spring 14 returns the latch to projecting position so as to break the circuit to the solenoid winding at contacts 13. This deenergizes the solenoid 37 and spring 48 returns valve 32 to its seat and unseats valve 33. As a result the supply of air to cylinder 20 is cut off from the source. The fluid pressure on piston 22 causes both pistons and the rack to move to the left and, as a=result, exert a closing force on the door through the links 17 and 16. At the same time fluid pressure escapes through the restricted passage of plug 26 and passage 25 into cylinder 20. This cylinder is open to the atmosphere through passage 47, casing 35 and the restricted port 36. The relative sizes of the passage in plug 26 and port 36 are such that a back pressure is built up in cylinder 20 so that only a limited amount of power is provided for closing the door. Just as the projecting end of latch 6 at its inclined surface strikes the keeper the projec-tin end of the piston rod 23 engages the slida le keeper 30. As a result cylinder 19 is cut off from cylinder 20 by the closure of passage 25. The remaining Y air in cylinder 20 continues to leak out through the port 36 reducing the back pressure against the pistons with the result that just as the door closes the engine exerts an additional force on the door to complete its closing movement and effect the latching thereof. Thus at the end of the door closing stroke the motor increases its closing force to overcome the final resistance of the door check and the resistance to closing offered by the door latch.

From the above disclosure it will be apparent that this invention resides in certain principles of construction and operation which may be embodied in other physical forms by those skilled in the art without departure therefrom. I do not, therefore, desire to be strictly limited to this disclosure as given in an illustrative sense but rather to the scope of the appended claims.

What I seek to secure by United States Letters Patent is:

1. The combination with a door and a lock for locking the door closed, of a motive device comprising aligned cylinders, pistons in said cylinders, a piston rod having a bore therethrough connecting the pistons into a rigid structure, means interconnecting the door and the piston rod, a source of fluid pressure, a connection between one of the cylinders and the source, an electro-magnetic valve, a connection between the source and the other cylinder through the valve, and circuit means controlled by the lock for energizing the electro-magnet valve when the lock is unlatched to energize the motor for exerting an opening force on the door.

2. The combination with a swinging door and a lock for latching it closed, of a differential fluid pressure engine connected to the door, said engine comprising aligned cylinders and pistons therein united by a piston rod having a port therethrough, a fluid pressure source, a connection between the smaller cylinder and the source, a connection between the larger cylinder and the source including an elcctro-magnetic valve, means for engage ing the end of the piston rod to close the passage therethrough, and circuit connections between the lock and the electro-magnetic valve.

3. The combination with a door and a lock for latching it closed, of a motive device connected to the door comprising cylinders of different diameters, apiston in each cylinder, a piston rod rigidly uniting the pistons having a bore therethrough, a restricted discharge port at one end of the bore, said piston rod projecting at the other end beyond the piston, a resilient member engageable by the projecting end of the rod, a passage connecting the larger cylinder with the atmosphere through a restricted port, a fluid pressure source permanently connected to the smaller cylinder, a second connection from the fluid pressure source including an electro-magnetic' valve to the larger cylinder and circuit connections between the lock and the electro-magnetic valve, the relative size of the restricted port in the passage of the piston rod and the restricted port in the passage from the'larger cylinder being such that a back pressure is built up in the larger cylinder by the delivery of air from the smaller cylinder in door closing movement.

4. The combination with a door and a lock for latching it closed, of a motive device connected to the door comprising cylinders of different diameters, a piston in each cylinder,

' a piston rod rigidly uniting the pistons having a bore therethrough, a restricted discharge port at one end of the bore, said piston rod projecting at the other end beyond the piston, a resilient member engageable by the projecting end of the rod, a passage connectlng the larger cylinder with the atmosphere through a restricted port, a fluid pressure source permanently connected to the smaller cylinder, a second connection from the fluid pressure source including an electro-magnetic valve to thelarger cylinder and circuit connections between the lock-and the clectro-magnetic valve, the relative size of I the restricted port in the passage of the piston rod near the on piston rod and the restricted port in the passage from the larger cylinder being such that a back pressure is built up in the larger cylinder by the delivery of air from the smaller cylinder in door closing movement, the proj ecting end of the piston rod engaging the resilient member near the end of the stroke of the pistons to cut oil the communication between the cylinders throu h the piston rod.

5. The combination with a swinging door and a lock for latching it closed, of a motive device comprising cylinders of different diameters, piston rod united pistons in the cylinders, said cylinders being normally in communication through a passage in the piston rod, means for closin the passage in the d of the stroke of the piston, a fluid pressure source and electro* magnetically controlled means for supplying air to the larger piston cylinder from the source, and circuit connections between the lock and the electro-magnetic valve.

6. The combination with a swinging door anda lock for. latching it closed, of a motive devicercomprising cylinders of different diameters, piston rod united pistons in the cylinders, said cylinders being normally incommunication through a passage in the piston rod, means for closing the passage in the piston rod near the end of the stroke of the piston, a fluid pressure source and electro-magnetically controlled means for supplying air to the larger piston cylinder from the source, circuit connections between the lock and the electromagnetic valve, and a permanent connection between the fluid pressure source and the smaller cylinder. .7

7. The combination with a door and a lock for latching it closed, of a differential fluid pressure engine connected to the door means for supplying aim to the engine including an electro-magnetic valve, circuit connectlons between the lock and the electromagnetic valve for controlling the supply of air to the engine, and means for buildingup a back pressure in one cylinder when air is being supplied tothe other cylinder during a portion of the stroke of the pistons. V

8.. The combination with a door and a lock for latching it closed, of a difierential fluid pressure engine connected to the door, means for supplying air to the engine including an-electro-magnetic valve,'.circuit connections between the lock and the electromagnetic valve for controlling the supply of air to the engine, means for building up. a

back pressure in one cylinder when air is being supplied to the other cylinder during a portion of the stroke of the pistons, and meansfor rendering said means for building up the back pressure inefl'ective during the final stroke of the pistons.

In testimony whereof I have hereunto set '1 my hand on this 25thdav of June, A. 1)., 1931 JOHN H. VANDER VEER. 

